My boyfriend winked at the local tour guide, who winked back: “Just if we get tourists from Pakistan, Afghanistan and Taliban”.

While the imposing hilltop fort in the middle of the Thar desert has not been invaded for centuries, round rocks and long tubes made of yellow sandstone still lie in wait on top of the 99 ramparts to be rolled down on approaching enemies.

The Jaisalmer fort only has one entrance, but stroll through it as a friendly tourist and you soon find yourself in a maze where Hindu and Islamic architecture have mingled over hundreds of years. Exploring the narrow winding streets that are flanked by charming, yellow sandstone houses, my boyfriend kept repeating how Jaisalmer was his highlight so far in India.

“This is my favourite!”

“Why?”

“It´s an old fortified city which has incredibly narrow cobbled streets with meandering little alleyways with people living on top of each other. And the place literally looks like a giant sand castle.”

He paused to breathe and then added: “And stuffed with bookshops!”

Today, the entire city of Jaisalmer is made up of 75% Hindu and 25% Muslims. 3,000 of the 75,000 residents live inside the fort. Perhaps not surprising, most of them rely on tourism for a livelihood.

There may not be anyone approaching the fort with bows and arrows any longer, but its foundations are crumbling under the many tourists. The fort is built on a foundation of clay, sand and sandstone. Due to poor drainage system, much of the increased water consumption of the 400,000 annual visitors seep into the ground beneath the fort. Today, the fort is among the World Monument Fund's 100 Most Endangered Sites.

Tourists are advised not to stay overnight in the fort to not put additional pressure on its foundations. A piece of advice that is in the interest for anyone to follow, and not only for heritage reasons. For purely selfish reasons as well, you should stay in one of the hotels in town. You see, most of them have roof top restaurants. So, come night-time, you can sip a boiling hot cup of milky tea and marvel at the most magnificent fort you could ever imagine.